Thursday, 19 August 2010

Vineyard Agronomy

Chardonnay with Iron deficiency

Pinot Noir with Magnesium deficiency

It is essential to analyse the soil and vine tissue to understand the availability of nutrients in the soil. Even though we are organic, and never use herbicides or pesticides, it is sometimes necessary to apply nutrients to the soil and the vines to address any significant deficiencies.

Agronomy is the application of various soil and plant sciences to soil management and crop production. To advise us on such matters we employ the services of John Buchan, an excellent agronomist who specialises in organic viticulture.

John has just analysed the results of some recent soil and tissue samples and it seems that generally the overall results are encouraging. Whilst pH levels, at around 7.8, are still high, they are slightly lower than when we first analysed the soil. pH is a measure of the acidity of the soil and is important as a high pH can "lock up" nutrients restricting their availability to the vines. 

It's important to recognise that plant nutrition is a balancing act, as over application of any single nutrient can cause antagonism with other nutrients. Our priorities for this autumn and next spring will be improve the levels of Magnesium, Manganese and Iron, which are still very low.

As can be seen on the examples above, the leaves on some of the vines are already showing signs of these deficiencies.

Wednesday, 18 August 2010

ITV arrive at the Vineyard

ITV filming at the Silent Pool

Earlier this week an ITV film crew arrived at the vineyard but sadly only to use it as a car park! They were there to film a new drama series called The Oakes which will appear on our screens early next year. The plot involves a girl who drowns in a lake. The Silent Pool is a local beauty spot adjacent to the vineyard where they filmed the drowning.

Filming started at 8.00am and didn't finish until late into the evening, which I'm told will result in only 10 minutes screen time. It's apparently a low budget film but there were at least 25 cars parked in the vineyard, a huge amount of technical equipment and excellent catering to keep everyone well fed!

Thursday, 5 August 2010

Powdery Mildew Flag Shoots

A flag shoot infected with Powdery Mildew

Powdery Mildew is one of the most widespread fungal diseases of grapevines in the world. It is characterised by ash-grey to white powdery growth on green tissue of the vine. If uncontrolled it can cause serious crop losses and impair wine quality. One spore of Powdery Mildew can multiply to 50 million spores in just 3 weeks!

Dormant buds can be infected and survive over winter. When these buds shoot they are deformed and covered with the powdery mildew spores. These shoots need to be removed and destroyed. We have come across several shoots this year but hopefully it isn't widespread.

Sulphur and Copper are traditionally used to control mildews on the vineyard. We are trying to avoid these treatments by using compost teas which populate the vines with friendly bacteria and fungi.